The present invention relates to alarm systems, and more particularly to an alarm system adapted for use with a master antenna television system.
Many establishments, such as motels, hotels and hospitals, have master antenna television systems which utilize a single antenna or single connection to a cable antenna system for the purpose of distributing television and radio frequency signals to a plurality of rooms which are equipped with individual television sets. Such systems will typically include one or more trunk lines which derive signals from a main cable using splitters. Power available from a single splitter will normally provide signals to approximately 10 or 15 television sets. Thus, in very large motels or hotels there will normally be a large number of trunk lines, with the sets attached to a particular trunk line being located within a relatively small area. For example, one trunk line may serve the television sets positioned in rooms within one floor of one wing of a motel.
The value of television sets stolen from such establishments, and particularly motels, numbers in the millions of dollars each year. Many thefts occur in situations in which personnel of the establishment being robbed are aware of the occurrence of the theft, but feel powerless to stop the act of thievery because they do not wish to confront the thief.
Various systems have been devised for the purpose of attempting to alert personnel to the occurrence of a theft. Generally, however, such systems have utilized a system of wiring completely separate and apart from the MATV system or, as in the case of U.S. Pat. No. 3,696,378, attempted to use the MATV System as part of a continuous loop system in which the lack of voltage is detected for signaling an alarm condition.